PERFORCE change 120769 for review

[Fredrik Lindberg]

http://perforce.freebsd.org/chv.cgi?CH=120769

Change 120769 by fli at fli_genesis on 2007/06/02 12:04:53

	- Add and use MDNS_PKG_MAX_LEN instead of 9000 
	- Cap max number of bytes received via TCP to MDNS_PKG_MAX_LEN 
	- Use IPv6 header size instead of IPv4 when calculating packet size.
	- Remove debugging macros that live in debug.h now. 

Affected files ...

.. //depot/projects/soc2007/fli-mdns_sd/mdnsd/stack_mdns.c#4 edit
.. //depot/projects/soc2007/fli-mdns_sd/mdnsd/stack_mdns.h#3 edit

Differences ...

==== //depot/projects/soc2007/fli-mdns_sd/mdnsd/stack_mdns.c#4 (text+ko) ====

@@ -24,27 +24,30 @@
  *
  */
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <errno.h>
-#include <strings.h>
-#include <string.h>
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/ioctl.h>
+#include <sys/uio.h>
+
 #include <net/if.h>
+#include <net/if_dl.h>
+
 #include <netinet/in.h>
 #include <arpa/inet.h>
+
+#include <errno.h>
+#include <fcntl.h>
 #include <ifaddrs.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
 #include <unistd.h>
-#include <sys/ioctl.h>
-#include <sys/sockio.h>
-#include <sys/uio.h>
-#include <net/if_dl.h>
-#include <err.h>
-#include <fcntl.h>
 
 #include "mdns.h"
 #include "stack_mdns.h"
+#include "debug.h"
 
 static int mdns_udp_open(struct mdns *, int);
 static int mdns_udp_close(struct mdns *, int);
@@ -105,16 +108,15 @@
 	error = ioctl(sock, SIOCGIFMTU, &req);
 	close(sock);
 /*
- * IP-header (no options) and UDP-header
- * XXX: Will there ever be ip-options present in multicast packets?
+ * IPv6-header and UDP-header
  */
-#define _HDR_OVERHEAD (20 + 8)
+#define _HDR_OVERHEAD (40 + 8)
 	if (error != 0)
-		md->md_maxpkgsz = 512;
+		md->md_maxpkgsz = MDNS_PKG_UDP_LEN;
 	else {
 		md->md_maxpkgsz = req.ifr_mtu - _HDR_OVERHEAD;
-		if (md->md_maxpkgsz > 9000)
-			md->md_maxpkgsz = 9000;
+		if (md->md_maxpkgsz > MDNS_PKG_MAX_LEN)
+			md->md_maxpkgsz = MDNS_PKG_MAX_LEN;
 	}
 #undef _HDR_OVERHEAD
 
@@ -872,8 +874,9 @@
 			pkg->p_len += n;
 			MDNS_BUFLEN(buf) = n;
 		}
-		if ((unsigned int)n < MDNS_BUFSZ(buf))
+		if ((unsigned int)n < MDNS_BUFSZ(buf) || pkg->p_len >= MDNS_PKG_MAX_LEN)
 			break;
+
 		buf = mdns_buf_alloc(md->md_bp, &pkg->p_buflist, 0, 0);
 		if (buf == NULL)
 			return (-1);

==== //depot/projects/soc2007/fli-mdns_sd/mdnsd/stack_mdns.h#3 (text+ko) ====

@@ -28,22 +28,8 @@
 #define _STACK_MDNS_H_
 
 #include <wchar.h>
-#include <assert.h>
-
 #include "stack_buf.h"
 
-/* Structure initialization protection */
-#define MDNS_MAGIC_COOKIE 0xcafebabe
-#ifdef DEBUG
-#define MDNS_INIT_SET(_md, f) (_md)->f = MDNS_MAGIC_COOKIE;
-#define MDNS_INIT_UNSET(_md, f) (_md)->f = ~MDNS_MAGIC_COOKIE;
-#define MDNS_INIT_ASSERT(_md, f) assert((_md)->f == MDNS_MAGIC_COOKIE);
-#else
-#define MDNS_INIT_SET(_md, f)
-#define MDNS_INIT_UNSET(_md, f)
-#define MDNS_INIT_ASSERT(_md, f)
-#endif
-
 /* Multicast DNS constants */
 #define MDNS_MCAST_INET	"224.0.0.251" /* IPv4 multicast address */
 #define MDNS_MCAST_INET6	"ff02::fb" /* IPv6 multicast address */
@@ -52,6 +38,7 @@
 /* Header constants */
 #define MDNS_PKG_LABEL_LEN	63
 #define MDNS_PKG_UDP_LEN	512 /* legacy udp length */
+#define MDNS_PKG_MAX_LEN	9000 /* Maximum packet length */
 #define MDNS_HEADER_LEN		12
 #define MDNS_QSET_HLEN		4  /* qset header length */
 #define MDNS_RRSET_HLEN		10 /* rrset header length */